mp/include/shaderService.h

//
// Created by jie on 2023/10/11.
//

#ifndef LEARNOPENGL_SHADERHELPER_H
#define LEARNOPENGL_SHADERHELPER_H

#include "glad/glad.h"
#include <filesystem>
#include <type_traits>
#include <glm/glm.hpp>

class ShaderService
{
private:
    unsigned int programId;

public:
    explicit ShaderService(const char* vSource, const char* fSource);
    explicit ShaderService(const std::filesystem::path &vertexShaderPath, const std::filesystem::path &fragShaderPath);
    void InitShader(const char* vSource, const char* fSource);
    bool CheckShader(unsigned int shaderIndex, bool isProgram = false);
    void Use();
    inline unsigned int GetId() { return this->programId; }
    template <typename T>
        requires std::is_same_v<T, bool> || std::is_same_v<T, int> || std::is_same_v<T, float> ||
                 std::is_same_v<T, glm::mat4> || std::is_same_v<T, glm::vec3>
    void SetUniform(std::string_view name, T value);
};

template <typename T>
    requires std::is_same_v<T, bool> || std::is_same_v<T, int> || std::is_same_v<T, float> ||
             std::is_same_v<T, glm::mat4> || std::is_same_v<T, glm::vec3>
void ShaderService::SetUniform(std::string_view name, T value)
{
    if constexpr (std::is_same_v<T, bool>)
    {
        glUniform1i(glGetUniformLocation(programId, name.data()), (int)value);
    }
    else if constexpr (std::is_same_v<T, int>)
    {
        glUniform1i(glGetUniformLocation(programId, name.data()), value);
    }
    else if constexpr (std::is_same_v<T, float>)
    {
        glUniform1f(glGetUniformLocation(programId, name.data()), value);
    }
    else if constexpr (std::is_same_v<T, glm::mat4>)
    {
        const auto index = glGetUniformLocation(this->programId, name.data());
        glUniformMatrix4fv(index, 1, GL_FALSE, &value[0][0]);
    }
    else if constexpr (std::is_same_v<T, glm::vec3>){
        glUniform3fv(glGetUniformLocation(programId, name.data()), 1, &value[0]);
    }
}

#endif // LEARNOPENGL_SHADERHELPER_H